cyberfish,
I apologize for arriving late to the discussion, and my comments will probably be moot since you've already migrated your e-mail. Your original request was for opinions on the pros and cons of using free, off-site apps (in general I assume, not just Google or e-mail specifically). Since no one really addressed the "cons", I'll attempt to do so now.
Well managed companies with skilled IT personnel do everything possible to safeguard and maintain full control over the company's private and valuable data. They never hand their data or related processes over to an outside operation over which they have little control and no legal recourse. It matters not if the service is free or has nifty features and a colorful icon. It simply isn't done. Period. End of discussion.
Now add the deplorable track record for most on-line apps, social networking and web 2.0 services in general* in maintaining anything even close to a secure, business-like environment, and the option of using free, off-site services becomes even less desirable.
Finally, factor in the cost of migrating back to in-house processes after the on-line service goes out of business (because they were free), starts charging high monthly rates (to avoid going out of business), or "evolves" their services in a way that conflicts with your organization's needs. ( And consider the very real possibility that there might not BE a way of migrating back.)
So, having said that, why do so many NPO's think on-line apps are a great way to go, other than the obvious free buy-in? I'm no psychologist but the following comes to mind.
First, many NPO's are not particularly well managed.
Second, most of the smaller ones have no experienced IT people nearby to point out the above-listed risks and disadvantages.
Third, and far more subtle, is that many people of all ages and organizational positions are relative newcomers to computers, networking and the Internet (let's say... less than 10 years.) Their experience is exclusively at the consumer level and they have no idea how serious networks are run. They honestly believe that a product is designed primarily for business use if it has the words "office", "pro", or "business" in its name. And they think it normal, acceptable and maybe even standard business practice to invite others to social sites that are crawling with malicious software, or to send e-mails with third party advertising at the bottom.
Finally, and I confess that I have trouble understanding this one, many NPO's treat their data as if it has no value at all. Formal, secure backup strategies are non-existent. Yet employees, volunteers and just about anyone else who gets into the building is welcome to copy private documents or database information onto a USB flash drive and share it with whomever they wish. From that perspective, I suppose it's perfectly acceptable to allow Google or anyone else to dig around in your e-mail, documents, spreadsheets and whatnot. But it's no way to run a business.
Hope that helps.
-ENO
*Yeah, I'm probably going to get flamed over that one. But if you'd like me to post all the gmail outages, twitter Trojans, facebook privacy violations, myspace screw-ups and related web 2.0 problems of the last year or so, I think I have a list around here somewhere.